Safety catch for elevators



Aug. 19 1924. 1,505,872

- A. DEERWESTER SAFETY CATCH- FOR ELEVATORS Filed July 6, 1923 2 Sheets-Sheet 1 Aug. 19,1924. 1,505,872

A. DEERWESTER SAFETY CATCH FOR ELEVATORS Filed July 6, 1923 2 Sheets-Sheet 2 ATTORNEY Patented Aug. 19, 1924.

UNITED STATES ALVA DEERWESTER,

SAFETY CATCH.

Application filed July 6,

has for its object the provision of a novel catch device which will automatically operate to catch and hold the elevator against dropping in case of breakage of the cable or the hoisting mechanism.

An important object is the provision of a device of this character which is entirely inactive while the elevator structure is in norma-l or proper condition but which acts in stantly to exert its catching and holding action in case of derangement of the hoisting machinery.

Another object is the provision of a device of this character which will be simple and inexpensive to manufacture and install, sim' ple in its operation, positive in action, eflicient and durable in service and a general improvement in the art.

With the above and other objects and advantages in View the invention consists in the details of construction to be hereinafter more fully described and claimed and illustrated in the accompanying drawings, in which:

Figure 1 is a vertical section through an elevator or mine shaft showing the elevator and illustrating the catch mechanism in its normal position,

Figure 2 is a similar view showing the cable broken and the parts in their holding position,

Figure 3 is a longitudinal sectional view on a considerably larger scale,

Figure 4 is a detail cross section at right angles to Figure 3 the view being taken on the line 44 of Figure 3,

Figure 5 is a vertical section on the line 5-5 of Figure 3,

Figure 6 is a detail perspective view of one of the catch members.

Referring more particulc rly to the drawings the letter A designates an elevator shaft or mine shaft against the sides of which I secure upright guides 10 which may be formed of angle bars, beams or any other similar structural elements and which have PATENT ()FFICE.

OF BUTLER, MISSOURI.

FOR ELEVATORS.

1923. crial NO. 6495935.

their confronting faces formed or equipped with retaining teeth 11 of a ratchet like na-- ture including inclined walls 12 and square shoulders 13.

The car or elevator B is moved by means of the usual cable C wound in or let out by the usual or any preferred hoisting mechanism. Secured upon the top of the car B is a frame structure 14: having a suitable hole or guide 15 through which the cable passes, and including laterally extending guides 16. Slidable through these guides are plungers 17 which have their outer ends carrying heads 18 formed with beveled ends 19 for co-operation. with the ratchet like teeth 11. The inner ends of these plungers project inwardly of the frame 14: and the plungers are normally urged outwardly by coil springs 20 which surround the plungers and which abut against the heads 18 and shoulders 21 on the frame.

Mounted within the upper portion of the frame 14 is a laminated spring 22 which has its ends bearing against the underside of the frame and which is normally bowed downwardly at its center. Encircling the central portion of the spring is a loop like yoke 23 to which the cable is attached by the means to be described. For supporting, bracing and guiding the spring in its flexing movement, 1 provide elongated loop like guides 24L which depend from the frame 14. and through which the spring passes. Pivoted on brackets 25 on the inside of the central arched portion of the frame 1a are angle levers 26 which have their lower arms pivotally connected at 27 with the inner ends of the plungers 17. Of necessity this connection must be of the pin and slot type to prevent binding. The upper arms of these angle levers are pivotally connected at 28 with links 29 which are pivoted at 30 on a bracket 31 which depends from the yoke 23.

While it is conceivable that various means might be provided for attaching the cable to the device, it is preferable that the cable be brought through a hole 32 in the top of the yoke 23 and that use be made of a filler block 33 fitting within the yoke 23 above the spring 22. This filler block is formed with a tapered opening 34 which receives the lower end of the hoisting cable C. In connecting the cable, the. lower end thereof is raveled out or frazzled where it is disposed within the opening 34:, and Babbit metal is then poured into this tapered opening' so as to mold about the raveled out end of the cable and provide a solid cone shaped mass 35 which will positively anchor the cable Within the block.

In the operation it will be seen that ordinarily the weight is borne by the block 33 and yoke 23 and the spring is flexed upwardly to a suflicient extent that the angle levers are in such position that the plungers 17 and heads 18 carried thereby are out of engagement with the teeth 11 on the guides. In case of breakage of the cable, the strain on the spring 22 will be relieved and this spring will bow downwardly, moving the angle levers 26 in such a way that the lower ends thereof will force the plungers outwardly until the heads 18 thereof engage the teeth 11. This will naturally result in catching and holding the elevator so that it cannot drop and cause injury to the occupants.

From the foregoing description and a study of the drawings it will be apparent that I have thus provided a simply constructed and easily installed safety device which will be inexpensive to make and positive in its action. of the parts and the simplicity of the entire mechanism it is apparent that there is very little to get out of order so that the device should have a long life and satisfactorily perform all of its functions.

While I, have shown and described the preferred embodiment of the invention it is of course to be understood that I reserve the right to make such changes in the form, construction and arrangement of parts as will not depart from the spirit of the inv-ention or the scope of thesubjoined claims.

Owing to the fewness described my invention I i'ng, a leaf spring within the arch and .en-. gaging thereagamst, retalnmg guide black ets of loop like formation on the arch ortion straddling the spring, a head carried by the lower end of the cable and located within said arch portion, said spring extending through and being rigidly carried by said head, and a link pivotally connected with the head andwith the inner ends of said angle levers. I

2. In an elevator mounting, including a frame on the elevator, means for connecting the hoisting cable to the frame comprising a head of open. frame like construc tion, a spring device within the head engaging the elevator frame, the elevator frame and the top of the head having openings for the passage of the cable, the lower end of the cable being fifrazzled out within the head,- and a mass of metal within the head embedding the frazzled out end of the cable.

In testimony whereof I afiix my signature.

ALVA DEERWESTER. i 

